Dimmers have become increasingly popular for controlling light intensity. Dimmers typically employ solid-state devices such as triacs, silicon-controlled rectifiers, or field-effect transistors for varying the phase angle of an applied a.c. sinusoidal voltage. Known dimmers are responsive to command signals directed at the dimmer in the form of radiant energy, typically in the infrared range. Infrared transmissive windows or sections allow the command signal to reach an IR receiver housed within the dimmer.
IR responsive dimmers allow for dimmer control systems in which an IR command signal can be “blasted” from one source of IR radiation for receipt by multiple dimmers. An example of a dimmer control system that uses infrared radiation to communicate command signals from one source of IR to multiple dimmers is the SPACER SYSTEM™ sold by Lutron Electronics Co., Inc. of Coopersburg, Pa. The SPACER SYSTEM™ utilizes a master control having an optically clear back cover that allows command signals from a source of IR radiation located within the master control to be “blasted” outwardly from the master control into control having an optically clear back cover that allows command signals from a source of IR radiation located within the master control to be “blasted” outwardly from the master control into the wallbox that houses the master control. The system also includes multiple dimmers housed in the same wallbox. Each of the dimmers includes an optically clear back cover and an internal IR receiver. The IR receiver of each dimmer receives infrared command signals that are blasted into the wallbox from the master control. The system is also disclosed in U.S. patent application Ser. No. 09/220,632, issued as U.S. Pat. No. 6,380,696, assigned to Lutron Electronics Co., Inc., the Assignee of this application.